Process for making pile fabric



Feb. 29, 1944. c L D 21; 2,342,746

PROCESS FOR MAKING PILE FABRICZ Filed Aug. 23, 1941' CAW ZSJ ZM v ATTORNEYS Patented Feb. 29 1944 UNITED STATES PATENT OFFIC raocass For: MAKING rm: FABRIC Charles Henry Maslaml, 2nd, near Carlisle, Pa. Application August 2:, 1941, Serial No. 408,122 4 Claims. (01. 28-75) ;The present invention relates to processes for treating, drying, curing and/or manipulating textile fiber, and producing pile fabric therefrom.

The present application is a continuation in part of my copending application Serial No. 366,354, filed November 20, 1940, for Textile dyeing and finishing method, apparatus and product.

A purpose of the invention is to create a loftier pile in a pile fabric such as a carpet or rug, and to produce a pleasing effect more economically.

A further purpose is to apply a resinous size to the fibers to be used for making the piles of pile fabrics such as carpets or rugs prior to spinning, cure the resinous size, spin the sized fibers into pile yarn and employ the yarn in the pile of a pile fabric, thus using the tendency of the sized fibers to return to their unspun condition to give increased loftiness to the pile.

A further purpose is to form artificial textile fiber of average diameter between. 27 and 75' microns into an unspun band, continuously size" the band with a resinous size such as'urea formaldehyde or acrylate resin, continuously cure the resinous size, spin the fiber into yarn, and form the yarn as the pile yarn of a cut pile fabric, the fiber in the cut pile having a tendency toreturn to its unspun condition due to the action of the resinous size, and thereby giving improved loftiness to the pile.

A further purpose is to size artificial textile fiber continuously and/or render'it water-repellent by handling the fiber as an unwoven band.

A further purpose is to progress artificial textile fiber in band form through an aqueous solution of urea formaldehyde, desirably maintained hot and uniform by recirculation from a heatedreservoir, and subsequently to dry, cure and wash the fiber, all as a' continuous process.

A further purpose is to terminate the drying of artificial textile fiber which has been subjected to treatment with a resinous sizing, at a convenience in illustration, satisfactory operavtion and clear demonstration of the principles involved.

Figure 1 is a diagrammatic front elevation of the preferred form of my novel sizing process.

Figure 2 is an enlarged fragment of the surface of the intaglio-engraved printing roll;

Figure 3 is a fragmentary section of Figure 2 on the line 3-3 thereof.

Figure 4 is a diagrammatic side elevation showing'the pick-up mechanism 23 which is desirably attached to the pre-wetting box.

Figure 5 is a .diagrammatic illustration of the chemical treatment box and reservoir with assoning, so that the stable condition of the fibers is moisture level of at least 12%, and preferably at least 15% of the dry weight of the fiber, in order to facilitate the spinning of the fiber into yarn.

A further purpose is to apply sizing, desirably urea formaldehyde, prior to spinnin to crimped artificial textile fiber of large diameter in order to assist in maintaining the crimp during spinning and to obtain greater covering power.

Further purposes appear in the specification and in the claims.

In the drawings no attempt has been made 'to illustrate all forms of the present invention. The single form shown has been chosen because of its the condition reached after the resinous sizing is fixed on the fiber. The fibers after spinning tend to return to their unspun condition in the cut pile to a much greater extent than when the fibers are untreated or treated by any other method,

thus assuring increased loftiness in the pile.

This invention is particularly useful in increasing the loft in a pile consisting wholly or in part of artificial textile fibers of large diameter, and especially those of average diameter between 27 and microns, which are specially suited for house furnishing fabrics of the type of fioor coverings and upholstery fabrics. The invention is particularly useful for rayon fibers such as regenerated cellulose (viscose or cuprammonium) although it may also be applied to cellulose ester fibers such as the acetate. Without the resinous sizing treatment of the present invention, many of these synthetic fibers tend to produce a pile yarn having less loft than one made from carpet wool.

inous size to the fiber in band form will follow printing of color on both sides oi. the band. During the printing, the steaming in the ager and the treatment in the fixing baths, certain opportunities develop for crimping forces to become efiective. Also in many cases the fiber ini- It is contemplated. that the application of resgilling.

tially supplied to the printing machine will have been previously crimped, for example by the be present during spinning-to maintain the crimp,-

whereas this is not true if the sizing is not applied until afterthe spinning of the fiber into As already explained, resinous sizing applied before spinningwill increase the covering power by setting the fiber in unspun condition, so that after spinning the fibers will tend to untwist, thus forming a loftier yam of greater coverin power.

The drafting incident to spinning has the desirable effect of removing any'slight unevennesses in color level which may remain in spite of the print dyeing, and also make it possible to combine with the lot, after color correction, a sample which has been run for color test purposes before color correction.

The term band is used hereinzto designate unspun fiber in continuous strip form. The band may either consist of artificial textile fiber in the form of a rope ,or bundle obtained from the filament extrusion machine after suitable treatment such as desulphurizing, bleaching and washing, or it may consist of a sliver coming from a raw preparation process such as carding, combing or The rope, bundle or sliver may come directly and continuously from the mechanism on which it was prepared or it may come rolled into a spool. ball, cake, roll or cheese.

It is considered that the best application of the invention will be to ropes or bundles of substantive continuous filament (that'is, filament having substantivity) which are not to be converted into staple fiber until after treatment by the present process.

For the above reasons proceed directly with the sizingor other desired chemical treatment as a step following the print dyeing during the continuous travel of the band. Less advantageously, however, the s zing or other chemical treatment can precedef; the print dyeing. It will also be understood that even where print dyeing is not being employed, continuous s zing or chemical treatment in accordance with the present processes may desirably be used.

In the present invention it, is preferred to employ urea formaldehyde. although any other suitable resinous sizing such as thiourea formaldehyde, acrylate, phenol formaldehyde, or the like mi ht be employed and the disclosure of resinous sizing herein is generic. Urea formaldehyde is much superior to other resinous sizings.

The resinous sizing, for example urea formaldehyde. desirably servesto maintain crimp as previously expla ned. The urea formaldehyde also tends to make the pile fibers of cut pile fabrics return to or approach their unspun condition as previously explained. imparting loi'tiness.

Unless precautions are taken in applying the urea formaldehyde, it will penetrate the fibers and markedly increase the brittleness. To prevent such increase in brittleness, T will preferably use only urea formaldehyde in an advanced stage of polymerization, in .which condition the resin it is very desirable to.

will not penetrate but merely coat the fibers, and will not increase the brittleness. 7

Example 1 Urea formaldehyde may desirably be applied to the fiber in an aqueous treating bath by passing the band of fiber through the bath.' The preparation of the liquid resin (or the unpolymerized liquid mixture of resin'ingredients) will preferably be as follows:

Formaldehyde and urea in proportions of about 1.8 molecular quantities of formaldehyde to 1.0 molecular quantity of urea are brought together at about 130 F. in a suitable quantity of water and in the absence of a catalyst. A pH of about 9v is maintained. When the product is condensed to the desired degree, a suitable catalyst such as ammonium acid phosphate is added and the resultant product is ready for application to the textile fiber. A treating temperature of 9,0 to

110 F. is recommended.

it is not ordinarily desirable to employ mo than 5% of urea formaldehyde on the weight of the fiber. Up to 5% of urea formaldehyde on the weight of the fiber may be employed without embrittlement if care is taken to see that-the urea formaldehyde coats without penetration.

In addition to the sizing, other suitable chemical treatments may be applied in the same bath or in a separate bath, such as finish coating, delustering, lubricating and waterproofing.

A special after treatment is employed to fix or cure the urea formaldehyde. The after treatment used will ordinarily be as follows:

i. Drying 3. Washing 2. Curing 4. Drying The initial drying will desirably be accom plished at a wet-bulb temperature not in excess" of 120 F. (the temperature of the moisture on the fiber) In-the initial drying, the fiber should reach practical dryness, that is 3% moisture or less of the weight of the fiber. The curing temperature should range between 270 and 300 F.,

at the most economical temperature; preferably about 212 F. wet bulb and 250 F. dry bulb.

Where the product under treatment is unspun fiber, the moisture content at the completion of the finaidrying operation is a matter of importance. When the product comes from the drier in substantially dry form and is subsequently converted into yarn by cutting into staple fiber lengths, if not already cut, drafting and spinning, it has been found that the fiber produced in accordance with the invention is difllcult to manipulate. Where the treatment with urea formaldehyde or other resin size as above described has been used, the fiber, if substantially dry, behaves like wire in carding and is practically unspinnable in that form. Lubrication with oil or with emulsion, and ordinary types of mois- This condtion can be corrected by exposure to moisture at room temperature for 38 to 48 hours, wiith some reduction in time if elevated temperatures are used. The present inventor has discovered, however, that the whole diiliculty can be avoided and the material rendered immediately and normally spinnable on either the woolen or the worsted system,ii the drying operation be terminated when the moisture content has been reduced to not less than 12%, and preferably not less than of the dry weight of the fiber. The upper limit of moisture content will normally be 131%? and preferably of'the dry weight of the Instead of urea formaldehyde resin, acrylate,

butyl, isobutyl and higher esters of acrylic acid;

polymers of alkyl alkacrylates such as the methyl, ethyl, propyl, butyl, isobutyl, and higher esters of methacrylic acid, ethacrylic acid, or the like; polyhydric alcohol esters of these acids such as diglycol methacrylate; and polymers of acrylonitrile or methacrylonitrile.

The acryiate resins may desirably be applied to the fiber in the form of dispersions in water or other mediums. It is desirable to employ dispersing agents such as alkyl naphthalene sulphonic acids or their alkali metal or ammonium salts, alkali metal or ammonium soaps, Turkey red oil, sodium petroleum sulphonate, Marseilles soap or the like. Protective colloids such as casein, gelatin, glue, soluble starch, gum tragacanth, gum acacia, gum tragon, sodium alginate, agar agar or the like may be used also; Catalysts such as example benzoyl peroxide, hydrogen peroxide and the like may be used.

Ea'rample Z vigorously mix 100 parts by weight of monomeric methyl methacrylate containing one part of benzoyl peroxide catalyst, with 500 parts of water containing 2% of dissolved gum tragacanth and a suitable dispersing agent such as alkyl naphthalene sulphonic acid.

A fiber band is passed through this dispersion held at room temperature, after which the band is squeezed, and dried and cured (polymerized) at about 212 F. in ovens l1 and 48.

If desired, the dispersion may be maintained at any temperature between 68 F. and 150 F. for a time up to 48 hours or longer before use to cause partial polymerization of the dispersed resin.

Example 3 vigorously mix 100 parts by weight of monomeric methyl acrylate with 400 parts of water containing 0.3 per cent of Marseilles soap, 0.5

. per cent of propylnaphthalene sulphonic sodium salt and 2 per cent of aqueous hydrogen peroxide catalyst. The fiber band is passed through the dispersion held at any desired temperature between 68 F. and 195 F., depending upon the desired degree of polymerization, before drying and curing in the ovens at about 212 F.

Example 4 Instead oi applying the acrylic resin as a dis-, persion, it may less desirably be used as a solution-in any suitable solvent, such as toluene or I acetone.

Example 5 The fiber band is passed through a 5% solution of polymerized methyl methacrylate in acetone, and the fiber band is dried in the air and then, with further curing of the resin, in the oven at 212 F.

The advantages concerning sizing with resin given in this application would in general apply rape of continuous filament, it will normally be cut into staple lengths, drafted and spun. If the fiber already is in the form of a silver or rovin8 of staple fiber, it will be drafted and spun. The fiber treated herein may be blended with any other suitable fiber as desired. If the fiber is in the form of a warp or warp unit, it may be used directly for weaving or-qther procedure of producing fabric (for example, by cementing to a backing for production of aLcemented pile fabric). The yarn may also be plied to combine several ends.

In the apparatus as shown in Figure 1, the material undergoing treatment is drawn from any suitable source here illustrated as a creel 20. The raw material is drawn of! in the form of a band and may, as already explained, actually be a rope, bundle, roving, sliver, or the like.- The band 2i may be, printed dry but will ordinarily undergo prewetting in the treatment box 22 from which it is withdrawn by a pick-up mechanism 23, later to be described, which as sists in forming a fiat band. A considerable quantity of band will normally remain fanfolded in the treatment box 22, being drawn out at a rate determined by the speed of movement of the rolls 23', which are operated by means not shown synchronized with the printing rolls. The prewetting box in the case of rayon will normally merely contain water, but in the case of wool a scouring agent followed by a suit able rinse may be employed at this point. From the treatment bpx 22 the fiat band 2| is carried over an' idler 24 to the printing mechanism 25 consisting of printing units 26, 21, 20, and 20 arranged one above another on a frame 20.

The printing units 25 and 28 print on the right-hand side of the upwardly directed span of fiber band shown in Figure 1, while the printing units 21 and 29 print on the left-hand side or this span. I

The printing units are described in detail in application Serial No. 366,354, filed November 20, 1940, for Textile dyeing and finishing, method,

apparatus and product, which is incorporated herein by reference, and no further detail of them will be given herein, as it is not important to the present invention.

Sufiice it to say that each printing unit includes an intaglio engraved printing roll 59, suitably of copper, which contactsthe fiber band. The roll 59, as seen in Figures 2 and 3, has channels extending over its entire surface. These color to the level of the circumference of the roll in any desired manner, each channel Ill contains substantially the same measured quantity of color. In, printing artificial textile fiber of large diameter, it has been found to be desirable to employ channels approximately 0.01 inch deep. and to use twenty-eight channels per inch on the circumference of the roll. This is merely suggestive and not stated as a limitation.

After the printing of color upon the fiber band,

the color will be desirably immediately fixed,

the method of fixing depending upon the particular dye used. Ordinarily the fiber band will pass directly through an ager or steamer in which it will be exposed to steam at a temperature depending upon the dyestuil, suitably 212 to 215 1". for a time of 4 to 5 minutes in the case of a vet dye, and at a somewhat lower temperature for a longer time, for instance 180 to 190 F. for 8 to 10 minutes, in the case of a direct or acid dye.

The finishing treatment of the dye will vary with the dyestuff as well known in the art. For example, with a vat dyestufi' th treatment may consist of oxidizing with an oxidizing'agent such as hydrogen peroxide and then passing through not soap .solution while in the case of a direct or acid dye there would normally be treatment with cold neutral soap solution followed by a rinse. :From the printer 25 the fiber band proceeds to dye-fixing mechanismstarting with an ager or steamer ii of any suitable manner, and normally supplied with steam by means-not shown.

As already explained the character of the fixing treatment will depend upon the dye used. In this example the'fiber band passes from the ager I successively through an oxidizer 33-, a soaper 34,

and rinse 3B and 36. Each of these treatment boxes 33 to 36 may be of any well-known type, and here are provided with feed rolls 31, driven in any suitable manner and carrying the fiber. hand between compartments 38 and 39, each of which has a partition 40 separating the outgoing froni the incoming portions of the fiber band.

From the dye-fixing mechanism the fiber band is progressed to the sizing box 4| in which a resin size, preferably urea formaldehyde is contained in solution or suspension. The most efilcient temperature of operation in the treatment box M is from 90 to 110 F. To maintain this temperature and to maintain uniformity of the treating liquor, the treating liquor in each compartment of the treatment box 4| is continuously drawn oif at a pump 42 (Figure 5) and connections 43 to a reservoir 44, jacketed at 45 by hot water. The reservoir 44 contains urea formaldehyde of the same'composition as that in the treatment box. Treating liquor continuously flows through the p pe connection 46 to the compartments of the treating box. The fresh treating liquor from the reservoir 44 is introduced by the pipe 48 on the outgoing side of each compartment of thetreatment box 4|, thus applying the countercur- ,rent principle. From the treating box 4| the fiber band desirably passes through a drier 41 of any suitable type and heated by any suitable means, not shown. The drier will normally operate at a temperature not exceeding 120 F. wet bulb. From the drier 41 the fiber band progresses to a curer 48 main tained at a more elevated temperature, suitably between 270 F. and 300 F. dry bulb. From the curer 48 the fiber band passes through suitable washing units, desirably consisting of a soaper 40 and rinsing boxes 50 and 5|. From the washing units thefiber band is carried to a drier I! preferably about 212' 1''. wet bulb and 250' 1". dry bulb. The fiber is withdrawn from the drier 52 befor its moisture content has dropped below about 12% and preferably before it has dropped 10 below of the .dry weight of the fiber. From the drier 52 the fiber band passes to any suitable take-up mechanism, here shown as a windup It. or directly to a preparation or spinning apparatus. a 15 Special precautions are taken to insure that the fiber band which comes to the printing mechanism is substantially of uniform thickness. If the fiber band were withdrawn from the liquid without taking any precaution in this respect, the effect of the surface tension of'the liquid would result in producing a circular or oval cross section of the band and the flattening action of the flattening rolls would produce a band much- 1 face of the lfi uld in the pick-up mechanism 2:;

the fiber band is carried intocontact with the moving surface 54 of a drum 55. It will be noted that the point of contact 58 with the drum 5! is below thesurface of the liquid. At the time contact between the fiber band and the surface of the drumis made, the fiber band is relatively spread out due to the action of the liquid. The

spread fiber band is then carried up on the surface of. the drum until it is above the surface of the liquid,adh'esion to the surface of the drum overcoming the} tendency of the fiber band to assume a circular or oval cross section when leaving the liquid. The drum surface is desirably of metallic screen wire 51 or other foraminated material so that liquid from the fiber band will drain through the drum as the band travels with 'the drum. The point at which the fiber band leaves the drum is well abovethe surface of the liquid. After leaving the drum the fiber band is flattened by pinch rolls and then is printed on both 'sidesby the printing mechanism.

It will beevident that the present invention produces pile fabrics with greater economy because of the greater covering power of the pile fiber and with improved appearance because of the increased loft of each pile tuft. These features are especially pronounced in cut pile fabrics 55 and find their greatest utility in carpets and rugs.

When reference is made herein to curing of a resinous size, it is intended to designate any curing operation, for example condensing or polymerizing the resin ingredients.

In view of my: invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the process shown.

. Having thus described my claim is new and desire to secure by Letters Patent is:

1. The process of producing improved pile 7 fabrics, which comprises forming artificial textile fiber ofv average diameter between 2'7 and '15 microns into an unspun band, continuously s zing the band with a resinous size while progressing the band lengthwise, continuously curing the resinous size while continuing the lengthwise operated at the most economical temperature,

invention, what I progression of the unspun band, spinning the fiber into yarn, and forming the yarn as the pile yarn of a cut pile fabric, the fiber in the cut pile having a tendency to return to its unspun con- .dition due to the action of the resinous size, and

, the band with urea formaldehyde while progressing the band lengthwise, continuously curing the urea formaldehyde while continuing the lengthwise progression of the unspun band, spinning the fiber into yarn. and forming the yarn as the pile yarn of a cut pile fabric, the fiber in the cutpile having a tendency to return to its unspun condition due to the action of the urea formaldehyde, and thereby giving improved loftiness to the pile.

3. The process of producing improved pile fabrlcs, which comprises forming artificial textile fiber of average diameter between 27 and 75 microns into an unspun band, continuously sizin the band with acrylate resin while progressing the band lengthwise, continuously curing acrylate resin while continuing the lengthwise I progression of the unspun band, spinning the .fiber into yarn, and forming the yarn as the pile yarn of a cut pile fabric, the fiber in the cut pile having a tendency to return to its unspun condition due to the action of the acrylate resin, and thereby giving improved loftiness to the pile.

4. The gocess of producing improved pile fabr'ics, whic the yam as the pile yarn of a cut pile fabric, the fiber in the cut pile having a tendency to return to its unspun condition dueto the action of the methyl methacrylate, and thereby giving improved loftiness to the pile.

CHARLES H.. MASLAND, 2ND.

the.

comprises forming artificial textile fiber of average diameter between 2'1 and 75 mi- 

